Another six municipalities in Attica were added to the areas that have reported cases of the West Nile virus.
Health authorities said on Wednesday that from May 31 until August 20 there have been cases reported in at least 39 municipalities, including Kallithea, Egaleo and Piraeus – compared to 10 last year.
Up until last week, the virus, which is carried by mosquitoes, had infected a total of 77 people, while five people have died.
The virus has also infected people in Viotia, Halkidiki, Thessaloniki, Evia, Imathia, Pella, Corinth, Kilkis and Rethymno on Crete.
The Center for Disease Prevention and Control (KEELPNO) is expected to release its latest report on Thursday.